I have hundreds of hours of Rotax 912 time, they run fine on 100LL with the correct MX being performed. Oil changes have to happen 2x as often but otherwise, it’s no big deal. Having an A&P that knows how to work on a Rotax is the key, as they aren’t a dinosaur Lycoming or Continental motor of the 1950s
Or for transport category you could just go turbine and avoid all of the archaic piston technology all together... again power plant aside, Tecnams are poorly constructed and designed aircraft.
I'm not saying you're wrong about the Tecam being poorly constructed. But Cape Air has ordered 100 of them, and they are sort of designed to Cape Air specs, and Cape Air has significant experience, and you'd think they would act as a check on quality control for the aircraft. Cape Air must trust (and insepct) that Tecam is doing the right thing.
About the turbine ... There is no fuel efficient 375HP turbine (although maybe the RR300 could be uprated to that level). So your choices are single turbine or two pistons. I'd rather be with two pistons. On the other hand, there are over 1,000 single engine planes flying behind a PT-6 and they've been doing it for over a decade (the TBM and the PC-12) and I think no one has ever died because of engine failure.
Will the FAA allow regularly scheduled airline flights in single engine aircraft in IFR?
Well I’ll agree to disagree about Tecnam products (partly because one of the ones I flew was involved with a fatal crash that lead to their grounding and withdrawal from service). I have heard too many horror stories from others as well about their lack of quality... it’s not like air operators have never made a mistake before ordering planes then removing them from their fleets afterwards.
I guess we’ll find out!
C172-M/N/P/R/S , PA-28-180, P2006T, PA-34-200T, B1900D, DH8A/C ERJ-145, CRJ-100/200, DH8D, CRJ-700/705/900, E-175/190, A319/320/321, 737-200/300/400/600/700/800/900ER/M8, MD-82/83, 757-200/300, 767-300, A330-300, 787-9, 777-300ER, F28-4000.